Anesthetic Fade in Intraoperative Transcranial Motor Evoked Potential Monitoring Is Mainly due to Decreased Synaptic Transmission at the Neuromuscular Junction by Propofol Accumulation

Abstract

Background We previously reported that normalization of motor evoked potential (MEP) monitoring amplitude by compound muscle action potential (CMAP) after peripheral nerve stimulation prevented the expression of anesthetic fade (AF), suggesting that AF might be due to reduced synaptic transfer in the neuromuscular junction.

Methods We calculated the time at which AF began for each of craniotomy and spinal cord surgery, and examined whether AF was avoided by CMAP after peripheral nerve stimulation normalization in each. Similar studies were also made with respect to the upper and lower limb muscles.

Results AF was observed in surgery lasting 160 minutes for craniotomy and 260 minutes or more for spinal surgery, and 195 minutes in the upper limb muscles and 135 minutes in the lower limb muscles. In all the series, AF could be avoided by CMAP after peripheral nerve stimulation normalization.

Conclusion AF of MEP occurred in both craniotomy and spinal cord surgery, and it was also corrected by CMAP after peripheral nerve stimulation. AF is considered to be mainly due to a decrease in synaptic transfer of the neuromuscular junction due to the accumulation of propofol because of the avoidance by CMAP normalization. However, it may be partially due to a decrease in the excitability of pyramidal tracts and α-motor neurons, because AF occurred earlier in the lower limb muscles than in the upper limb muscles.

Keyword

transcranial motor evoked potential monitoring - compound muscle action potential - anesthetic fade - craniotomy - spinal surgery

• References

• 1 Rothwell J, Burke D, Hicks R, Stephen J, Woodforth I, Crawford M. Transcranial electrical stimulation of the motor cortex in man: further evidence for the site of activation. J Physiol 1994; 481 (Pt 1): 243-250
• 2 Morota N, Deletis V, Constantini S, Kofler M, Cohen H, Epstein FJ. The role of motor evoked potentials during surgery for intramedullary spinal cord tumors. Neurosurgery 1997; 41 (06) 1327-1336
• 3 Zhou HH, Kelly PJ. Transcranial electrical motor evoked potential monitoring for brain tumor resection. Neurosurgery 2001; 48 (05) 1075-1080 , discussion 1080–1081
• 4 Lyon R, Feiner J, Lieberman JA. Progressive suppression of motor evoked potentials during general anesthesia: the phenomenon of “anesthetic fade.”. J Neurosurg Anesthesiol 2005; 17 (01) 13-19
• 5 Ying SW, Goldstein PA. Propofol suppresses synaptic responsiveness of somatosensory relay neurons to excitatory input by potentiating GABA(A) receptor chloride channels. Mol Pain 2005; 1: 2
• 6 Shimizu M, Yamakura T, Tobita T. et al. Propofol enhances GABA(A) receptor-mediated presynaptic inhibition in human spinal cord. Neuroreport 2002; 13 (03) 357-360
• 7 Baars JH, von Dincklage F, Reiche J, Rehberg B. Propofol increases presynaptic inhibition of ia afferents in the intact human spinal cord. Anesthesiology 2006; 104 (04) 798-804
• 8 Kakinohana M, Fuchigami T, Nakamura S, Kawabata T, Sugahara K. Propofol reduces spinal motor neuron excitability in humans. Anesth Analg 2002; 94 (06) 1586-1588
• 9 Tanaka S, Kobayashi I, Sagiuchi T. et al. Compensation of intraoperative transcranial motor-evoked potential monitoring by compound muscle action potential after peripheral nerve stimulation. J Clin Neurophysiol 2005; 22 (04) 271-274
• 10 Tanaka S, Watanabe T, Takanashi J, Oka H, Hashimoto R, Akimoto J. Effect of compound muscle action potential after peripheral nerve stimulation normalization on anesthetic fade of intraoperative transcranial motor-evoked potential. J Clin Neurophysiol 2021; 38 (04) 306-311
• 11 Ugawa R, Takigawa T, Shimomiya H. et al. An evaluation of anesthetic fade in motor evoked potential monitoring in spinal deformity surgeries. J Orthop Surg Res 2018; 13 (01) 227
• 12 Ushirozako H, Yoshida G, Kobayashi S. et al. Impact of total propofol dose during spinal surgery: anesthetic fade on transcranial motor evoked potentials. J Neurosurg Spine 2019; 1-9
• 13 Tanaka M, Shigematsu H, Kawaguchi M. et al. Muscle-evoked potentials after electrical stimulation to the brain in patients undergoing spinal surgery are less affected by anesthetic fade with constant-voltage stimulation than with constant-current stimulation. Spine 2019; 44 (21) 1492-1498
• 14 Smith I, White PF, Nathanson M, Gouldson R. Propofol. An update on its clinical use. Anesthesiology 1994; 81 (04) 1005-1043
• 15 Metz CE, Goodenough DJ, Rossmann K. Evaluation of receiver operating characteristic curve data in terms of information theory, with applications in radiography. Radiology 1973; 109 (02) 297-303
• 16 Cedzich C, Taniguchi M, Schäfer S, Schramm J. Somatosensory evoked potential phase reversal and direct motor cortex stimulation during surgery in and around the central region. Neurosurgery 1996; 38 (05) 962-970
• 17 Tanaka S, Akimoto J, Hashimoto R, Takanashi J, Oka H. Cutoff points, sensitivities, and specificities of intraoperative motor-evoked potential monitoring determined using receiver operating characteristic analysis. J Neurol Surg A Cent Eur Neurosurg 2019; 80 (02) 102-108
• 18 Suzuki K, Kodama N, Sasaki T. et al. Intraoperative monitoring of blood flow insufficiency in the anterior choroidal artery during aneurysm surgery. J Neurosurg 2003; 98 (03) 507-514
• 19 Chen X, Shu S, Bayliss DA. Suppression of ih contributes to propofol-induced inhibition of mouse cortical pyramidal neurons. J Neurophysiol 2005; 94 (06) 3872-3883
• 20 Leite LF, Gomez RS, Fonseca MdeC, Gomez MV, Guatimosim C. Effect of intravenous anesthetic propofol on synaptic vesicle exocytosis at the frog neuromuscular junction. Acta Pharmacol Sin 2011; 32 (01) 31-37
• 21 Jonsson Fagerlund M, Krupp J, Dabrowski MA. Propofol and AZD3043 inhibit adult muscle and neuronal nicotinic acetylcholine receptors expressed in xenopus oocytes. Pharmaceuticals (Basel) 2016; 9 (01) 8